Microsoft shipped a wave of Copilot updates for September 2026, and several of them genuinely change how everyday Word, PowerPoint, and Excel work gets done. If your company pays for Microsoft 365 Copilot — or you keep hearing about it and want to know what is actually new — this guide covers the six features worth learning now, based on Microsoft's September 3 release notes and the feature walkthroughs published this month.
1. Interactive slides in PowerPoint
The headline feature. Copilot in PowerPoint can now build interactive slides — instead of a static wall of bullets, you get elements your audience can respond to, and Copilot restructures content on the fly. The practical win: paste a rough outline, ask for an interactive summary slide, and let Copilot handle the layout thinking you used to do manually.
Try it: open PowerPoint → Copilot pane → describe the slide you want and include the word "interactive." Refine with follow-ups ("make the comparison a clickable toggle") rather than starting over.
2. Answer cards in Copilot Chat
Copilot's chat responses now surface answer cards — structured, glanceable blocks (dates, owners, figures, links) instead of paragraph soup. This lands alongside the updated chat home screen and streamlined response layout Microsoft described in its September 3 release notes. The upshot: answers about meetings, documents, and people are faster to scan and easier to act on.
3. The rebuilt Notebooks UI
Copilot Notebooks — Microsoft's answer to NotebookLM — got a rebuilt interface this month. Notebooks let you pin a set of files, chats, and pages, then query only that collection, so answers stay grounded in your project materials instead of your entire mailbox. If you tried Notebooks earlier and bounced off, the new UI is the reason to retry: source management and page organization are dramatically cleaner.
Best use: one notebook per project or client. Same pattern that works in NotebookLM — grounded answers with your sources, but inside your Microsoft 365 tenant.
4. Cowork cost controls
For organizations experimenting with Cowork (Copilot's multi-agent workspace), September adds cost controls — admins can cap agent usage so an enthusiastic team does not burn the monthly budget in a week. This is aimed at IT, but it matters for users too: expect fewer blanket bans on agent features now that spending is controllable.
5. Shareable skills
You can now package a working prompt-plus-setup as a skill and share it with teammates. Built a Copilot routine that formats meeting notes exactly how your team likes? Share it as a skill instead of pasting prompt text into Teams. This quietly solves the biggest Copilot adoption problem: most people never learn what to ask. Now the one person who figured it out can distribute the recipe.
6. New Word and Excel refinements
The September wave also includes updates across Word and Excel — tighter draft-and-refine loops in Word and improved data handling in Excel. Individually small, but they compound: the pattern across all six features is Copilot shifting from "chatbot bolted onto Office" to structured, shareable, admin-manageable workflows.
How to actually adopt this (without the overwhelm)
- Pick one feature per week. Start with answer cards (zero setup), then Notebooks, then interactive slides.
- Steal skills before writing your own. Ask whoever runs Copilot adoption at your org what shared skills already exist.
- Anchor everything in real files. Copilot's quality jumps when it works from your actual documents rather than open-ended questions — Notebooks make that the default.
The bottom line
September 2026 is one of the strongest Copilot update months yet: interactive PowerPoint, a genuinely usable Notebooks, and shareable skills address the three biggest complaints — static output, ungrounded answers, and the "I don't know what to ask" wall. If you have access, this is the month to give it a second look.